The present invention relates to a device for displacing a gondola or a similar receiving or working device that is vertically adjustably suspended with, for example, a carriage supported on a guide rail or a boom.
From German Auslegeschrift 24 04 294 a carriage with a boom that is displaceable along the edge of the roof and has a gondola suspended therefrom is known. In this manner it is possible to laterally displace the gondola by displacing the carriage, and by changing the length of the cables supporting the gondola the gondola is lifted or lowered so that, for example, for cleaning a facade substantially any location on the facade is reachable. However, the supply of energy to the displaceable carriage is often extremely difficult. In most cases it is necessary to entrain a cable and, in order to avoid damage to the cable by the carriage wheels, this cable must be guided in a special manner or it is necessary to install sensitive sliding contacts on the roof of the building. Furthermore, for the known device a relatively large boom is required so that the gondola can be suspended from the edge of the roof. It is furthermore disadvantageous that the carriage which is provided with the boom and at least two drive motors, has a high weight which must be supported by a correspondingly heavily constructed support structure and that the carriage often can only be manuevered with difficulties around roof structures and around corners. Thus, the field of use of such device is relatively limited.
It is therefore an object of the present invention to provide a device for displacing a gondola which can be universally used and also is of a relatively small construction and requires only little expenditure for its design so that it can be manufactured economically. It is especially desirable that for the displacement of the carriage and for the height adjustment of the gondola stationary drive units are to be provided so that the supply of energy to these drive units can be achieved without problems and that entrained cables or sliding contacts are not required, while on the other hand a high operational safety and an easy handling of the device is possible.